Today marks 100 years since the birth of Benjamin Britten, one of the great composers of the 20th century.

Britten’s compositions span classical music forms, from large-scale symphonic scores to songs and choral works. He first achieved international fame in 1945 with the acclaimed premiere of his opera Peter Grimes. One hundred years after his birth, more operas by Britten are performed worldwide than by any other composer born in the 20th century, and he is widely credited with founding a new English-language opera tradition. He also introduced generations of children to music through such works as Noye’s Fluddeand The Young Person’s Guide to the Orchestra, which is now the focus of an iPad app. 'His music really gets under your skin, which makes him stand out,' says Royal Opera Music Director Antonio Pappano.

Benjamin Britten's five Canticles, written between 1947 and 1974 and to be staged at the Royal Opera House this July, almost perfectly book-end his post-war career. But what are canticles and how do they relate to the composer's operatic output?

The loosely-defined term 'canticles' originally meant a short prayer-like song, but was probably best known to Britten from the Magnificat and Nunc Dimittis texts that feature in the Anglican evening service. His texts span widely across English literature, drawing on a medieval Chester Miracle Plays, Jacobean metaphysical poetry and poems by Edith Sitwell and T.S. Eliot. All but the last have biblical inspiration, but none are specifically liturgical. Are these works prayers, or did 'canticle' have a separate significance for Britten?

The Canticles are a quintet of chamber works for a range of instrumentation, but their one constant is a tenor part. Each was written for Britten’s partner and muse Peter Pears. Performed together they present a powerful celebration of the composer's unique musical language.

Canticle I was written in memory of Reverend Dick Sheppard, founder of the Peace Pledge Union (a committed pacifist, Britten had been a member since its formation in 1934). Britten selected 17th-century poet Francis Quarles's 'My Beloved is Mine', an adaptation of the Song of Solomon: in Britten's hands a serenely radiant paean to love. First performed by Pears and Britten, it seems intended as an overt declaration of their relationship, a testament to both their joint artistic creativity and their personal commitment to each other.

Written in the wake of Billy Budd, Canticle II was composed between late 1951 and early 1952 and is a potent miniature opera for alto, tenor and piano created from a 15th-century Chester Miracle Play telling the story of Abraham and Isaac. Written for and dedicated to contralto Kathleen Ferrier (who created the title role in The Rape of Lucretia in 1946), her part is now more commonly sung by a counter-tenor. Britten later drew on Canticle II for his War Requiem, in the setting of Wilfred Owen's bitter retelling of the biblical story.

1954's Canticle III was another operatic pendant, following the premiere of The Turn of the Screw by just a few months. The Canticle is an aching, plangent outpouring of grief, setting Sitwell's The Raids, 1940: Night and Dawn. Its scoring for tenor, horn and piano recalls the sonority of Britten's 1943 Serenade; both were written for the brilliant horn player Dennis Brain. Britten wrote the Canticle for a memorial service for the young pianist Noel Mewton-Wood, who had taken his life the year before.

Seventeen years separated Canticle IV from its predecessor. Britten's setting of Eliot's The Journey of the Magi is written for alto, tenor, baritone and piano, the three male voices characterizing the kings on their wearying journey. Joining Britten and Pears in the premiere were counter-tenor James Bowman and bass-baritone John Shirley-Quirk, both regular collaborators with Britten.

Canticle V, written 1974, was Britten's first work after heart surgery the previous year had left his right hand partly paralysed; its scoring for tenor and harp is a poignant reminder that Britten's piano-playing days were over. It was written for the great Welsh harpist Osian Ellis, for whom Britten wrote his 1969 Suite for harp. Britten dedicated this last Canticle to William Plomer, the librettist for Gloriana and the Church Parables, whose death in 1973 had left Britten deeply shaken. He once more turned to Eliot (one of the few poets he continued to read after his surgery), choosing his mysterious early work The Death of St Narcissus.

The impassioned spirituality of each of the Canticles, and that they were all written for Pears, suggests that their significance for Britten, whatever its explicit cause, was deeply personal. From the impassioned devotion of Canticle I to the destructive obsession with beauty of Canticle V, these innately dramatic works seethe with an intensity that belies their simple forces. Neil Bartlett and Paule Constable face a challenge in staging them – but a rewarding one.

Britten's Canticles run in the Linbury Studio Theatre from 10 - 12 July 2013. All dates are sold out, though returns may become available.